Field of the Invention
The invention relates to an adjusting device for adjusting, a sheet transport cylinder in a sheet-fed rotary printing machine, depending upon various thicknesses of printing material.
Such an adjusting device is described in the published German Patent Document DE 39 02 923 A1, wherein an outer cylindrical or jacket surface of the sheet transport cylinder is provided with an outer or jacket film or foil, the outer diameter of which is variable by a variable-height element disposed under the outer film or foil and on a surface of the sheet transport cylinder. The outer film or foil is fixed by an adjusting device to at least one clamping point of the sheet transport cylinder so that a change in the outer diameter of the outer film or foil is effected by the adjusting device. The adjusting device can be operated manually or by a servodrive, for example, a pneumatic servodrive. In the case of a sheet-fed rotary printing machine having many printing units and therefore many sheet transport cylinders, an unacceptably long machine stoppage and refitting time is needed to change the outer diameter of the sheet transport cylinders manually. Although the refitting times can be shortened by using the servodrive, it would have to be integrated into the rotating sheet transport cylinder. This is firstly very complicated to implement in construction terms with regard to the power supply, for example, of a compressed air connection to the servodrive, and secondly is not possible at all in certain cases, for example, because the installation space needed in the sheet transport cylinder for the integration of the servodrive is not available.
Diagonal register adjusting devices described in German Patent DE 465 246 and German Patent Documents DE 34 00 652 C2 and DE 40 13 003 A1 represent only further prior art, and do not correspond to the generic type of adjusting device mentioned in the introduction hereto, and, in these devices, the axis of rotation of the sheet transport cylinder is adjusted to a following position which is skewed with respect to the initial position.
It is accordingly an object of the invention, therefore, to provide an adjusting device for a sheet-fed rotary printing machine wherein the adjustment is dependent upon various printing-material thicknesses, the adjusting device providing improved construction preconditions for remote operation.
With the foregoing and other objects in view, there is provided, in accordance with one aspect of the invention, an adjusting device for adjusting a sheet transport cylinder in a sheet-fed rotary printing machine, depending upon various printing-material thicknesses, comprising a mounting support for mounting the sheet transport cylinder so that a rotational axis of the sheet transport cylinder is adjustable from a first axial position, which corresponds to a given printing-material thickness, to a second axial position, which corresponds to another printing-material thickness and is axially parallel to the first axial position.
In accordance with another feature of the invention, the mounting support comprises at least one eccentric bearing having an eccentricity.
In accordance with a further feature of the invention, a movement path described by an axis of rotation during an adjustment thereof from the first to the second axial position corresponds to a line which determines a change in cylinder nips, which, in terms of size, is effected at least approximately to the same mutual extent, the nips being formed by the sheet transport cylinder together with adjacent cylinders.
In accordance with an added feature of the invention, the sheet transport cylinder is disposed between another sheet transport cylinder and an impression cylinder.
In accordance with an additional feature of the invention, the rotational axis of the sheet transport cylinder, both in the first and in the second axial position thereof, extends axially parallel to an axis of rotation of an adjacent impression cylinder.
In accordance with yet another feature of the invention, adjusting directions lie at least approximately on a bisector of an angle determined by the axis of rotation of the sheet transport cylinder and axes of rotation of other sheet transport cylinders adjacent to the first-mentioned sheet transport cylinder.
In accordance with a concomitant aspect of the invention, there is provided a sheet-fed rotary printing machine having at least one adjusting device for adjusting a sheet transport cylinder, depending upon various printing-material thicknesses, comprising a mounting support for the sheet transport cylinder so that a rotational axis of the sheet transport cylinder is mounted so that it is adjustable from a first axial position, which corresponds to a given printing-material thickness, into a second axial position, which corresponds to another printing-material thickness and is axially parallel to the first axial position.
The sheet transport cylinder is thus mounted so that the rotational axis thereof can be adjusted from a first axial position (initial position), which corresponds to one printing-material thickness, into a second axial position (following position), which corresponds to another printing-material thickness and is axially parallel to the first axial position.
The adjusting device according to the invention is particularly well suited for remote operation, because if an actuating drive is used to operate the adjusting device, the actuating drive can be arranged in a stationary manner and externally to the sheet transport cylinder. In the case wherein the actuating drive is constructed as a pneumatic operating cylinder, fixing it to a frame of the sheet-fed rotary printing machine arranged beside the sheet transport cylinder is advantageous, because an operating cylinder arranged in this way can be connected to a compressed air source in a straightforward manner via hose lines.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in an adjusting device for a sheet-fed rotary printing machine, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, wherein: